1. Field of the Invention
The present invention relates to a dust collection unit for use in a vacuum cleaner, and more particularly, to a dust collection unit for use in a vacuum cleaner which is constructed such that air flow path within a main body of the vacuum cleaner can be simplified while using a cyclone method of collecting dusts.
2. Description of the Prior Art
A vacuum cleaner is constructed such that air containing foreign substances is sucked into a main body of the vacuum cleaner using a suction force generated from the main body in which the foreign substances are in turn filtered out, and the air filtered clean is then discharged to the exterior of the main body.
To this end, a motor for generating the suction force and the like are installed within the main body of the vacuum cleaner. A filter means for filtering out the air to be sucked therein is also installed within the main body of the vacuum cleaner. A dust collection bag formed of paper is generally used as a conventional filter means. The dust collection bag allows only the air to pass therethrough but the foreign substances such as dusts to be collected therein.
However, after the foreign substances such as dusts and the like have been collected in the dust collection bag, the dust collection bag with the foreign substances contained therein is generally discarded. Thus, waste of material is brought about. In particular, there is a critical disadvantage in that the dust collection efficiency of the vacuum cleaner is further lowered as the dusts are collected in the dust collection bag.
In order to solve the above problems, a cyclone type dust collection unit has been developed. The cyclone type dust collection unit allows spiral flow to be created within a casing thereof when the air containing foreign substances is introduced into the casing.
As shown in FIG. 1, at one side of a main body 1 of a vacuum cleaner is installed a dust collection unit 2 which is constructed such that a primary dust collection using the cyclone method and a secondary dust collection using a filter can be performed. Accordingly, when the vacuum cleaner is operated, air containing foreign substances, which is sucked up through a suction nozzle 4, is introduced through an extension tube 6 and a connecting hose 8 into the main body 1 of the vacuum cleaner.
As shown in FIGS. 2 and 3, the air introduced through an inlet port 21 into the dust collection unit 2 is formed into spiral flow within a casing 22. Relatively heavy foreign substances fall downwardly due to their own weight. The air from which the heavy foreign substances have been removed is introduced into a filter 23, and is then exhausted through an outlet 24 formed on an upper end of the filter. The filter 23 is installed on a bottom surface of a cover 25 for substantially opening and closing the casing 22. Such collection unit is advantageous in that the relatively heavy foreign substances can be removed through the primary dust collection using the cyclone method and even fine dusts can also be completely filtered out through the secondary dust collection using the filter 23.
Air flow after the outlet will be described in detail with reference to FIG. 3. As shown in the figure, the outlet 24 is provided on a top surface of the dust collection unit 2. Accordingly, the air discharged through the outlet 24 is guided along a connection duct 26 which is constructed to connect the outlet 24 and a motor housing H contained within the main body of the vacuum cleaner above the dust collection unit 2. Accordingly, the connection duct 26 for connecting the outlet positioned on the top surface of the dust collection unit 2 and the motor housing H positioned lower than the dust collection unit within the main body of the vacuum cleaner is formed in a vertically downward direction.
However, such a conventional structure has the following disadvantages: Since the connection duct 26 should be used for connecting the dust collection unit 2 and the motor housing H, any suction loss may be generated at their respective connecting portions. Since this suction loss results in substantial reduction of the suction efficiency of the vacuum cleaner, it has an adverse influence on the performance of the vacuum cleaner. Furthermore, since the connection duct 26 is additionally installed, the number of parts is increased and the assembly process becomes complex. Thus, there are problems in that the production costs are increased and the productivity is lowered.